CDNA CLONING, GENE CHARACTERIZATION AND 13Q14.3 CHROMOSOMAL ASSIGNMENT OF CHC1-L, A CHROMOSOME CONDENSATION REGULATOR-LIKE GUANINE-NUCLEOTIDE EXCHANGE FACTOR

We report the characterization of a new gene mapped at chromosome band 13q14.3 telomeric to the retinoblastoma gene. This gene, designated C HC1L (for chromosome condensation 1-like), is composed of 14 exons spa nning 30 kb of genomic DNA and encodes a ubiquitously expressed 3-kb m RNA. The N-terminal half of the deduced amino acid sequence shows stro ng homology with the seven tandem repeat structure of the regulator of chromosome condensation RCC1, which acts as a guanine nucleotide exch ange factor (GEF) protein for the Ras-related GTPase Ran. CHC1L appear s to be a new member of the RCC1-related GEF family, (C) 1998 Academic Press.